Re: [PATCH 0/4] meson: parse TAP output generated by our tests

[Patrick Steinhardt <ps@pks.im>]

On Fri, May 23, 2025 at 12:03:24PM +0200, Patrick Steinhardt wrote:
> On Wed, May 21, 2025 at 02:26:23PM -0700, Junio C Hamano wrote:
> > So the four patches are now sitting somewhere in 'seen'.  Is it the
> > one that causes this failure, I have to wonder?
> > 
> > 
> > https://github.com/git/git/actions/runs/15169816296/job/42656836511#step:4:2113
> > 
> > It is curious that only osx-meson is affected.
> 
> Ah, interesting. Seems like macOS has since updated to a newer version
> of Meson, so it now uses the TAP parser. And there are some tests that
> only execute on macOS and that cause us to emit output to stdout/stderr,
> which will thus break the TAP format.
> 
> I'll have a look and will send a newer version soonish.

Okay, the problem actually isn't the TAP format -- Meson copes with the
broken output, but I'll fix it regardless in the next version of this
patch series. The problem is that we have a test that unexpectedly
passes on macOS:

    ▶  868/1023 - git grep .fi a                             UNEXPECTEDPASS

The test in question is this one:

    test_expect_failure !CYGWIN 'git grep .fi a' '
        git grep .fi a
    '

The test passes if '.' matches a NUL byte, which we expect to only
happen on Cygwin. 064eed36c7f (config.mak.uname: only set NO_REGEX on
cygwin for v1.7, 2025-04-17) mentions that this behaviour was probably
imported from FreeBSD, which makes me wonder whether macOS eventually
also inherited the same code given its BSD lineage.

I think we probably want something like the below patch to fix this. We
could also have a prereq, but that prereq would look almost the exact
same as the test. It does make me question the value of the test itself
as the behaviour is completely platform specific.

Patrick

diff --git a/t/t7815-grep-binary.sh b/t/t7815-grep-binary.sh
index b7d83f9a5de..55d5e6de17c 100755
--- a/t/t7815-grep-binary.sh
+++ b/t/t7815-grep-binary.sh
@@ -63,7 +63,7 @@ test_expect_success 'git grep ile a' '
 	git grep ile a
 '
 
-test_expect_failure !CYGWIN 'git grep .fi a' '
+test_expect_failure !CYGWIN,!MACOS 'git grep .fi a' '
 	git grep .fi a
 '
 
diff --git a/t/test-lib.sh b/t/test-lib.sh
index 6ce8570226c..fef522327f2 100644
--- a/t/test-lib.sh
+++ b/t/test-lib.sh
@@ -1636,6 +1636,9 @@ fi
 # Fix some commands on Windows, and other OS-specific things
 uname_s=$(uname -s)
 case $uname_s in
+Darwin)
+	test_set_prereq MACOS
+	;;
 *MINGW*)
 	# Windows has its own (incompatible) sort and find
 	sort () {